E60 530d 535d. E61 530d 535d. Oil in the unit will dissolve any marker pen marks. For BMW’s only the last 7 digits are required, for 2.7 TDV6 Discovery 3’s and 4’s it is not required at all. See the pictures to understand why you should never buy a used unit as you cannot know the condition of the internals without first opening them up.
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